Number Prefixes

Number prefixes are prefixes that are derived from numbers or numerals. They are used to create some words you will encounter. Recognizing these prefixes and the numbers they represent will help you to learn and better understand the meanings of such words

Here are prefixes that represent the numbers 1 though 10. Next to each prefix are examples of words that are formed using the number prefix, along with the meanings of the words.

1

mono

monologue

A long speech or performance given by one person.

monorail

A railroad track that has only one rail.

1

uni

unicorn

An imaginary animal that has one horn.

unicycle

A pedaled vehicle that has one wheel.

2

bi

bicycle

A pedaled vehicle that has two wheels.

biennial

An event that occurs every two years.

2

du

duet

A piece of music written for two singers or musical instruments.

duplex

A house divided into two units with separate entrances.

3

tri

triangle

A plane figure that has three angles and three sides.

tricycle

A pedaled vehicle that has three wheels.

4

quad

quadrangle

A plane figure that has four angles and four sides.

quadruple

A number or amount four times as great as another.

5

penta

pentagon

A plane figure that has five angles and five sides.

pentathlon

An athletic contest that consists of five events.

5

quint

quintet

A group of five persons or things.

quintuplets

Five children born at the same time to the same mother.

6

hexa

hexagon

A plane figure that has six angles and six sides.

hexagram

A six-pointed star.

7

sept

septenary

A period of seven years.

septennial

An event that occurs every seven years.

8

oct

octet

The first eight lines in a sonnet.

octopus

A saltwater animal with eight arms.

9

nov

November

The ninth month of the year in the ancient Roman calendar.

novena

Nine days of prayers or services.

10

deca

decade

A period of ten years.

decathlon

An athletic contest that consists of ten events.

You can expand your vocabulary by recognizing these number prefixes when they appear at the beginnings of words.